1. Field of the Invention
The present invention relates to an assembling apparatus for a heat exchanger.
2. Description of Background Art
A fin unit of a heat exchanger is shown in FIG. 28. Multiple fins 10 are stacked with predetermined clearances, and U-shaped pipes 11 are inserted through pipe holes 10a of the fins 10. The pipes 11 are expanded to fix the fins 10 thereto. Ends of the pipes 11 are mutually connected by U-shaped connecting pipes (not shown) so as to run heat conductor therethrough.
An assembling apparatus for the heat exchanger is known.
The conventional assembling apparatus has a pipe inserting unit.
Firstly, as shown in FIG. 29, multiple fins 10 are stacked onto a stack pin holder 13 by piercing stack pins 12 therethrough. The stacked fins 10 are laid on a supporting table 14 (see FIG. 30). Next, the pipe 11, which is held by guides 15, is pushed by a pusher 16 to insert the pipe 11 into the pipe holes 10a of the fins 10. Thus, the pipe 11 can be automatically inserted thereinto.
However, the conventional assembling apparatus has the following disadvantages.
The pipe 11 is generally made of copper having a higher thermal conductivity. However, the copper pipe is a bendable metal pipe. When the copper pipe 11, which is longer than one meter, is pushed through the pipe holes 10a of the fins 10, the ends of the copper pipe 11 are apt to be bent downward by gravity. If the ends of the pipe 11 are bent, it is very difficult to align the ends with the pipe holes 10a and the guides 15, so that it is sometimes impossible to insert the pipe 11 therethrough.
The sizes of the fins 10 are not fixed because of manufacturing accuracy. Therefore, when the stacked fins 10 are laid on an upper face of the supporting table 14, the pipe holes 10a of the fins 10 are vertically shifted relative to one another. With this shift, the end or ends of the pipe 11 come into contact with an edge of a pipe hole 10a, so that the insertion is sometimes made impossible, or the pipe holes 10a are sometimes damaged.
And the stacked fins 10, which are laid on the supporting table 14, are apt to transform because the fins 10 are made of an aluminum sheet.